Flip v twist locks? I have tripods with both systems, and they're both fine. Some people report possible issues with flip locks catching on cords, clothes. Don't use this as a differentiating parameter.

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Cheers,Damien

Flip lock will loosen overtime. One of my cheap Velbon will not lock any more after 20 years. All of my Gitzo still lock after the same amount of time and a lot more usage!